// accumulate example
#include <iostream>     // std::cout
#include <functional>   // std::minus
#include <numeric>      // std::accumulate

int myfunction (int x, int y) {return x+2*y;}
struct myclass {
	int operator()(int x, int y) {return x+3*y;}
} myobject;

int main () {
	int init = 100;
	int numbers[] = {10,20,30};

	std::cout << "using default accumulate: ";
	std::cout << std::accumulate(numbers,numbers+3,init);
	std::cout << '\n';

	std::cout << "using functional's minus: ";
	std::cout << std::accumulate (numbers, numbers+3, init, std::minus<int>());
	std::cout << '\n';

	std::cout << "using custom function: ";
	std::cout << std::accumulate (numbers, numbers+3, init, myfunction);
	std::cout << '\n';

	std::cout << "using custom object: ";
	std::cout << std::accumulate (numbers, numbers+3, init, myobject);
	std::cout << '\n';

	return 0;
}
